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The purpose of this paper is to use an evaluation of a micro-place-based hot-spot policing implementation to highlight the potential issues raised by data quality standards in the recording and measurement of crime data and police officer movements.

The study focusses on an area of London (UK) which used a predictive algorithm to designate micro-place patrol zones for each police shift over a two-month period. Police officer movements are measured using GPS data from officer-worn radios. Descriptive statistics regarding the crime data commonly used to evaluate this type of implementation are presented, and simple analyses are presented to examine the effects of officer patrol duration (dosage) on crime in micro-place hot-spots.

The results suggest that patrols of 10-20 minutes in a given police shift have a significant impact on reducing crime; however, patrols of less than about 10 minutes and more than about 20 minutes are ineffective at deterring crime.

Due to the sparseness of officer GPS data, their paths have to be interpolated which could introduce error to the estimated patrol dosages. Similarly, errors and uncertainty in recorded crime data could have substantial impact on the designation of micro-place interventions and evaluations of their effectiveness.

This study is one of the first to use officer GPS data to estimate patrol dosage and places particular emphasis on the issue of data quality when evaluating micro-place interventions.

We investigate the causal relationships between volatility implied in Major Market Index (MMI) options and its component stocks' options from January, 1987 to October, 1989. We find that MMI implied volatility Granger causes component stock implied volatility for all twenty component stocks, which is consistent with the hypothesis that changes in volatility in index options markets leads volatility in underlying component (cash) markets. When we further analyze the sample by subperiod, we find that the causal relationships are insignificant in the period after the October 1987 crash, which is consistent with the hypothesis that exchange and regulatory actions taken after the crash weakened the influence of index options markets on cash markets. Trading strategies and programs involving stock index options and futures have been blamed for increasing volatility of the stock market. Indeed, trading in index futures and options markets has been blamed for much of the drop in stock prices in the crash of October 1987. After the crash, regulators took several actions to reduce the influence of futures and options market volatility on cash market volatility. If regulators' fears were legitimate and their efforts were successful, the volatility linkage between index options markets and their underlying cash markets should have been weakened. This paper provides two important contributions to our understanding of the volatility implications of index options markets. First, we examine the causality relationships between index and component stock implied volatility to assess whether or not changes in volatility in the index option market lead changes in volatility in the underlying component stock markets. Second, we test whether the causal relationships differ before and after the October 1987 crash to assess whether or not regulatory actions after the crash caused a change in these relationships. We measure volatility using implied standard deviations (ISDs) from options on the Major Market Index (MMI) and its component stocks. We form time series of ISDs for both the MMI and its component stocks, and then apply Granger causality tests to the series. For the full sample period of January 1987 to October 1989, we find that changes in index ISDs do Granger cause changes in component stock ISDs for all twenty component stocks, evidence consistent with the notion that volatility in index option market leads volatility in the component (cash) market. When we analyze the sample by subperiod, however, we find that the significant Granger causality holds only in the period before the October 1987 crash. Post‐crash subperiods show insignificant causality relationships, which suggests that efforts taken by exchange officials and regulators to reduce the influence of volatility in the index options and futures markets on cash market volatility were successful. The remainder of the paper is structured as follows. In Section I we discuss the potential for causal relationships between index option markets and their component markets and review related literature. Section II contains a discussion of our methodology and a description of our data. Section III contains a discussion of our results and Section IV concludes.

Motivation can serve as the engine that turns intention into action, and, as such, is indispensable in the early phase of the entrepreneurial process, where opportunity recognition and exploitation are key. However, research in this area has so far shed a selective spotlight on specific facets of entrepreneurial motivation, whereas the consideration of basic motives has been widely neglected. Hence, the purpose of this paper is to illuminate the basic motivational foundations of one core aspect of entrepreneurial behavior, namely opportunity recognition.

The study examined how motivation influences the process of recognizing and exploiting entrepreneurial opportunities in a sample of 312 managing directors and managing partners of small and medium-sized enterprises. Opportunity recognition and exploitation were assessed by two different measures: one evaluating the objective number of recognized and realized business opportunities, the other assessing the perceived proficiency in identifying and exploiting entrepreneurial opportunities. Implicit and explicit facets of basic motivation were measured using a comprehensive assessment of human needs.

Findings show that entrepreneurs' achievement motive is an important driver in both the identification and exploitation of opportunity. The power motive affects the perceived ability to exploit business opportunities. Interestingly, the explicit affiliation motive showed an inhibitory effect on the perceived ability of opportunity identification, whereas implicit affiliation motive is affecting the number of recognized and realized business opportunities positively.

This research clearly highlights the preeminence of basic motivational factors in explaining individual early-stage entrepreneurial behavior, making them a prime target for training interventions.

This paper reports the main findings of an evaluation of an intensive four‐week policing operation along a single bus corridor, aimed at reducing the extent of crime along the bus route. The evaluation, which adopts a mixture of quantitative evaluation techniques, demonstrates that the operation was successful both in increasing officer arrest rates (up to four times for the officers who worked on the scheme), and also in reducing crime levels for particular crime types, namely assault and theft from vehicle, up to 400m from the route. A conceptual discussion is provided as to how to measure the effectiveness of an operation with no geographically predefined action area and to define the relationship between action areas and displacement or diffusion zones. Consequently, this evaluation examines both the influence of the scheme within a predefined distance from the route, and also proposes a method for determining the likely range of influence of the scheme in terms of physical distance.

The purpose of this paper is to examine how the combined crime rate and staffing levels of a patrol area affect patrol officers’ productivity. Specifically, the author identified and analyzed two macro-level correlates of patrol officer productivity: reported violent crimes per officer and reported property crimes per officer (a beat’s “crime-to-cop” ratios).

Using hierarchical linear modeling, the author estimated the effects of a patrol area’s violent crimes per officer ratio and property crimes per officer ratio on the annual number of traffic citations, warrants, misdemeanor arrests, and felony arrests generated by patrol officers (n=302). The author also examined the effect of these crime-to-cop ratios on a more advanced productivity metric.

The results suggest that a patrol area’s rate of property crimes per officer is associated with a moderate decrease in an officer’s annual number of traffic citations, warrant arrests, and misdemeanor arrests; a patrol area’s rate of violent crimes per officer is also associated with a moderate decrease in an officer’s annual number of traffic citations; and a patrol area’s rate of violent crimes per officer is associated with a moderate increase in an officer’s annual number of warrant and misdemeanor arrests. Notably, the crime-to-cop ratios are not correlated with a more sophisticated patrol productivity metric.

The author analyzed data from a mid-sized US police department that uses a generalists policing style. It is unknown if these results translate to smaller or larger police departments, as well as those agencies practicing a specialized policing style.

The findings suggest that police scholars should not only recognize how the crime-to-cop ratios of a patrol area might impact patrol officer productivity, but also incorporate more sophisticated metrics of patrol officer activity in future studies. These findings likewise signal to police practitioners that an area’s crime-to-cop ratios should be considered when allocating officers and other resources across patrol areas.

To the authors knowledge, this is the first study to identify and examine the link between a patrol area’s crime-to-cop ratios and patrol officer productivity.

The purpose of this paper is to cumulate published empirical studies (1980-2009) on the relationship between individual variables and entrepreneurial status. The authors categorize repeatedly analyzed determinants into six perspectives (trait, cognitive, affective, intentions, learning, and economic), review empirical findings for each determinant and each perspective, investigate trends in the field, and propose avenues for future research.

The authors categorize determinants into one of the six paradigms and review findings for 46 repeatedly studied variables from 131 studies. Support for each variable, publication outlets chosen, and temporal trends in exploring entrepreneurial intentions, entrepreneurial status or differences between entrepreneurs and other individuals are analyzed.

Prior studies have focused on trait and economic perspectives with strong support, followed by the learning and intentions perspectives. The affective perspective is a still under-researched, yet growing field. Most articles were published in the 1990s. The emphasis on theoretical perspectives varies over decades. Directions for future research include integrating the perspectives (e.g. across the cognitive and affective domain), testing the temporal stability of influences, and developing and testing cross-level models that incorporate contextual influences.

The paper complements prior reviews and meta-analyses by picturing the breadth of the field and adding important points to the research agenda.